The present invention relates to a tip for an insertion device. More specifically, the invention is directed to a curved tip for an insertion device such as a catheter. The surface profile of the novel tip of the invention is completely curved and includes a generally parabolic tubular surface profile with an insertion end that assumes a generally circular surface profile.
A catheter is usually inserted through the skin of a patient by use of a sharp instrument, such as a needle. In many applications, the needle extends through the catheter wherein the point of the needle is adjacent to and extending slightly beyond the tip of the catheter. The needle pierces the skin of the patient to form an opening and the tip of the catheter follows the needle into the opening.
Traditional catheter tips generally have straight edges and blunt insertion ends. The bluntness of traditional tips impedes the forward progress of the catheter into the opening in the skin. The force required to insert a blunt ended, straight edged catheter tip into the skin, which is also known as xe2x80x9ctransition force,xe2x80x9d is generally sufficiently high to cause pain to the patient upon insertion.
Attempts have been made to reduce the transition force required to insert a catheter into the skin of a patient. An example of such a catheter is shown in U.S. Pat. No. 4,588,398. In this patent, the tip of the catheter is angular, although still with straight edges and a blunt insertion end.
It has been found that there is a need for a catheter tip that provides for the smooth and easy transition from a needle to a catheter as the device moves through the skin, to reduce the transition force during insertion of a catheter into a patient. The present invention satisfies this need.
The present invention is directed to an insertion device, such as a catheter, including a tip having a hollow, substantially radial cross sectional configuration and a substantially parabolic longitudinal configuration with a longitudinally circular tip curvature. The outer wall of the novel tip of the invention is completely curved, and contains no straight or angled outer walls within the length of the tip. The inner wall of the tip defines a substantially straight passageway through which a piercing device such as a needle may be inserted.
An embodiment of the present invention provides an insertion device that reduces the transition force required to insert the device into the skin of a patient.
An embodiment of the present invention also provides a tip for an insertion device having an entirely curved outer wall in the longitudinal dimension.
An embodiment of the invention further provides a catheter tip configuration which is thin enough to reduce the above-referenced transition force yet tough enough to eliminate splitting, tearing, or bunching of the catheter tubing material during insertion.
An embodiment of the present invention provides a catheter tip with a smoothly convex outer wall.
Other embodiments and advantages of the present invention shall become apparent to those skilled in the art upon a review of the following detailed description of the preferred embodiments and the accompanying drawings.